1. Field of the Invention
The present invention generally relates to a centrifugal pump, having a structure for chopping material entering the inlet of the pump. More specifically, the invention relates to a fish mincer pump which includes a chopper or shear plate and cutter knife associated with the chopper or shear plate on the inlet of the pump and a novel and unique mincer plate and a cutter knife or cutter knives associated with the mincer plate in the inlet of the pump and in inwardly spaced relation from the chopper or shear plate and cutter knife in order to mince fish waste parts such as fish heads and internal components that are to be discharged into the ocean into a 1/2 inch maximum solid size in order to comply with regulations. which require that fish waste to be discharged into the ocean must. not include components exceeding a maximum dimension of 1/2 inch. The mincer plate has a plurality of openings extending therethrough and oriented substantially throughout the entire area of the plate with each of the holes being not greater than 1/2 inch in diameter with the cutting knives associated with the mincer plate being on one or both sides of the mincer plate and having sharpened leading edge components in the form of bevelled edges to provide cutting edges which moves along the surfaces of the mincer plate to assure that all fish waste passing through the mincer plate will not exceed 1/2 inch in maximum dimension since the holes in the mincer plate and the thickness of the mincer plate does not exceed 1/2 inch. By the introduction of the mincer plate and cutter knives mounted on the impeller shaft of the pump in inwardly spaced relation to a conventional chopper plate and a cutter knife associated with the outer surface thereof which is also supported on and driven by the impeller shaft, existing centrifugal pumps with a chopper unit can be readily converted to a centrifugal pump with the mincer plate and cutter knives thereby providing an efficient and effective structure for chopping fish waste into small particles which meet regulations for pumping fish waste into the ocean.
2. Description of the Prior Art
In the fishing industry, current practice involves discharge of fish waste resulting from processing of the catch directly back into ocean. The fish waste is normally deposited in a holding tank and the fish waste along with water entraining the waste is pumped from the holding tank into the ocean. The pump is a centrifugal pump having the capability of pumping the slurry formed by the fish waste and water and usually includes a chopping assembly in the inlet. The chopping assembly includes a chopper plate stationarily mounted in the inlet and a rotatable cutter knife associated with the outer surface of the chopper plate to chop fish waste. The chopper plate utilizes four relatively large, arcuate openings defined by four radial spokes with the rotating knife chopping or shearing the fish waste. However, this structure does not chop the fish waste into maximum size 1/2 inch components that will satisfy present regulations that require all particles of fish waste discharged into the ocean to be no larger than 1/2 maximum size. It is also well known to provide meat grinding devices in which meat is chopped and then extruded through a perforated plate. The following U.S. Pat. Nos. are relevant to this field of endeavor.
43,520 PA1 348,132 PA1 412,557 PA1 429,850 PA1 3,667,692 PA1 4,003,521 PA1 4,512,523
None of the patents listed above disclose the concept of utilizing a mincer plate and cutter knife or knives associated with the inlet of a centrifugal pump used for discharging fish waste into the ocean.